Let-off mechanism for looms



Dec. 2, 1930. R. A. KE ARSLE.ZY

LET-OFF MECHANISM FOR LOOMS Filed Aug. 2'7, 1929 4 shets sheet l //v VENTOF?! ATTORNEY.

R. A. KEARSLEY 1,783,719

LET-OFF MECHANISM FOR LOOMS Dec. 2, 1930;

Filed Afig. 27, 1.929 4 Sheets-Sheet 2 ATTORNEY Dec. 2, 1930. R. A. KEARSLEY 1,783,719

LET-OFF MECHANISM FOR LOOMS Filed Aug. 27, 1929 4 Sheets-Sheet 3 Dec. 2, 1930.

R. A. KEARSLEY LET-OFF MECHANISM FOR LOOMS 4 Sheets-Sheet 4 Filed Aug. 27, 1929 //VI/ENTOR ATTORNEY Connected to the pawl carrier 8 at 11 is an actuating rod 12 which may be appropriately reciprocated from any going part of the loom and as shown in the present instance is given its reciprocating movements through a pin 13 connected to one of the lay swords, as, for instance, by a riser 14 secured to the lay rock shaft 15. The actuator 12 is provided with a slot 16 which engages the pin 13 so that the actuator is susceptible of lost 7 motion. The pawl carrier 8 is normally unreduction mechanism between the ratchet wheel 7 and the warp beam, and as this is clearly shown and described in the Roper patent hereinbefore mentioned, and'may be of usual type, its description here is deemed unnecessary, since the details thereof form no part of the present invention.

Extending from the pawl carrier 8 is a stop 20 which is adapted to engage a cooperating stop 21 (Fig. 3) adjustably supported on an arm 22 which may be loosely mounted on the shaft 6 or a part co-axial therewith. From the construction thus far described it will be apparent that should the arm 22 be raised or lowered, it will alter the position of the stop 21, and consequently govern or control the idle or retracting stroke of the pawl carrier 8 to thereby vary the amount of warp let-off from the warp beam.

Mounted at each side of the loom, and shown in the present instance above the warp beam, is a bracket or support 23, which may be adjusted in the vertical plane by means of the bolts 24 which pass through slots 25.

Eachof thebrackets 23 carries a guide- Way 26 in which is mounted a block 27 adapted for sliding movement towards and from the front of the loom, and mounted in the blocks 27 at opposite sides of the loom is a warp tension equalizer 28 which may be con? stituted as a roll about which the warp passes from the warp beam to the weaving instrumentalities. V

The warp tension equalizer is normally under the influence of a weight to maintain uniform tension on the warp passing about it, and in the present instance of the invention the warp tension equalizer or the block 27 in which it is mounted is connected to a flexible member 29 shown in the present instance as a sprocket chain which passes about a guide or sprocket wheelv 30 mountedon a rearwardly projecting portion 31 of the bracket 23. .The flexible member 29 then passes frontwardly of the loom and over a sprocket wheel 32 mounted on a transversely extending shaft 33 which is itself carried bet-ween the two brackets 23 at opposite sides of the loom. The flexible member 29 passes downwardly from the sprocket wheel 32 over a guide sprocket, 34 mounted on the loom frame and at its lower end the flexible member 29 is connected toa weighted lever 35 on which is mounted a weight 36 which may be adjustable longitudinally of the lever 35. The lever 35 is mounted for rocking movement on the loom frame at 37 and to the hub portion ofthe lever 35 the flexible mem ber is connected as at 38. If desired in some cases the hub portion of the lever 35 is provided with a projection 39 carrying a pin 40 which bears upon one side of the flexible member 29, the construction being such that the flexible member 29 is constantly under the influence of the weight 36 to exert a pull upon the warp tension equalizer 28 in a direction to impart uniform tension on the warp. i

he flexible member 29 may be connected to the warp tension equalizer to exert its con- .stant stress thereon under the action of the weight 36 in any suitable manner, but as herein shown the sliding block 27 is provided with a lug 41 to which the end portion of the flexible member 29 may be secured by a bolt orpin 42. i

In accordance with the present invention the function of the warp tension equalizer is to exert a constant and uniform tension on the warp under the stress of the weight 36 and consequently the warp coming from the warp beam is directed in runs about the warp tension equalizer. To this end the bracket 23, as indicated in Fig. 4, is providedwith a bearing 43 in which is supported a warp director or guide 44. The mounting for the guide 44 is contrived to direct the lower run of thewarp a in parallelism with the upper run of, the warp a about the warp tension equalizer, the result being that the stress of the warp tension equalizer under the action of the weight 36 will normally tend to elongate the loop of the warp and the parallel runs thereof. a

The warp tension equalizer is thus mounted for movement towards and from the front of the loom, or in a substantially horizontal acting, through thehflexibl'e mem'ber29, and

8;]and; since the amount of rotation of the since the stress-ofithe weight, remainsconstant throughout the weaving operation the tension ofthe. warp remams uniform and constant, regardless, of the amount of Warp let-ofi fromithe warp-beam by its positive rotative movement Mounted on the transversely extended shaft 33 at the side;- of the loom opposite the m flexible member 29--isa sprocket wheel 45,

and passing over thefsprocket wheel 45 is the flexible: member qorzsprocket chain, 46

which extends; downwardly; and; has secured to it ahoolrAJZ the ,lower end 01% which is engaged with a pin 4'8 asgindicated in Fig; 2,

which extends from thearm22, the constructien being such that the warp tension equalizerQSismoved towards and from: the front @of the loom it will actuatethe shaft- 33 throughithe'flexible member:29r and cause the flexible-n1jember orchain 46 to rise or fall-in accordance with the direction of 'movementof the shaft33, thereby determining the positionof the arm 22 and thestop '21 connected therewith, and "consequently governing the extent olf'ithe id-le stroke of the pawl carrier warpbeam by thepositive letr-oft is governed of let oft-i's equal zer; 1

by the extent of idle-strokeof the pawl ca'r rier, =,it-will benotedat-onceithatthe amount under control of the warpi'tension It; is: desirable that the warpitensionequal; izer shall remain parallel to ,the axisof the warp beam throughout thewm'ovementsl of the equalizer, and since the-warp tensioning weightni-n the illustrated vform of the invention, is Connected to: one end of the equalizer bythe. flexible member 29, itiseXpedientthat theflexiblefmemberQQ beformed as a sprock et chain so that itmay rotate the'transversely extending. shaft '33:; and likewise the flexible connection46 is formed as a second procket chain the upperendwhereof 1s connected to the tension equalizer For the block 27 at the side of the loom opposite: the sprocket chain 29,ias indicated more clearly in Figs.;2 and 6-,

vwhileits lower portion is connected'tofthe positive let-off control arm 22, ashereinbefore described. The result isvthat 'as the warptension equalizer moves towards and from the front of the loom and thus controls the amount of let-ott-without variation in warp tension, it will remain parallel to-the axis ofthe warp beam through the means described. Thdplaneofi the warp-between the equalizer and Q-front 'ot the loom'should be maintained in substantial parallelism with thelower-run of the warp;betw'een the guide roll 44 and equalizer 28, and since the frontward lead ot the warp-from the equalizer may vary under; different weaving conditions or in different looms, thebrackets 23which support the tension equalizer are adjustable to bring the irontward lead of theuwarp into or screw 56 (Fig. 5)

the. desired pa ans relation with, the lower therefrom by simply taking out the guide roll j44 temporarily. Thus in starting to weave with a new warp zitis usually the jpraci 'tive torun the loom and let-ofi for a short time until the frontward lead of the warp plane becomes establishedjand any broken 7 ends pieced up, whereupon the brackets'23 carrying the guide-roll may be adjusted to bring the two runs of thewarp leading about.

the equalizer into parallel relation. V V During the beat up and formation ofthe shed the warp issubjected to a sudden impulse or bump especially on the beat up, H

andto compensate for this effect upon] the warp tension equalizer the sliding block 27 inwhichtheiwarp tension equalizer is mounted, is -provide'dxwith a ,check which, while 7 permittingthe necessaryqgive to the warp equalizer during; the shed-formation and the bump of the beat up, will retard the-warp V tension-equalizerfrom sudden movement towards and 'fromthefront of the loon'n thus contributing to the maintenance'of the uniform tension in; the; warp throughout the weaving operation; I e l i As one ccnvenient form of check for the above purpose, and as shown i-nlFign5, the

block has mounted thereon at 49 a check arm 50 provided with an eccentric portion 51 havingteeth 52which are engaged with ,the

teeth 53 on a block '54,and. the check arm :50- is normally under the influence of a spring 55v one endoi which is connected to the check arm 50 and the other to an adjusting device The under sideof the block 54 is preferablyprovided with a friction pad 57 which bears upon thesurface of the guide 26 with the fresultthat while the friction pad 57 will permit thewarp -tension equalizer and its block mounting to move towards and from" i the frontof the loom under the uniform stressof the weight 36, itwill serve to check the bump during shed formation and the beat up. Y

It may be desirable at times to vary the" action of the friction pad, that is, to make it ice more or less in accordance with the character of the cloth being. woven, or other conditions,

and to this end the block 27 has arecess 58 in which theblock 54 is mounted for a limited v amount of longitudinal movement, and in orderto adjustthe position ofthe block 54 forthe desired conditions there is an adjusting'device or screw 59 at each end ofthe recess 58, whereby adj ustmentpf the block 54 the the

warp is wound, a positive let-elf for actuating the warp beam to let-off tn warp, a warp tension equalizer mounted for move: lent to wards and from the front of the loom, means for directing the warp in parallel runs about the warp tension equalizer from full to empty warp beam that the equalizer may exert unva-rying tension on the warp loop throughout the weaving operation, a weight normally active upon the warp tension equalizer in a 5 direction to maintain uniform tension on the warp throughout the weaving operation, and means governed by movement of the equalizer toward and from the front of the loom to vary the amount of let-ell from the warp beam without changing the uniform warp tension.

2. In a let-oil mechanism for looms, the combination of the warp beam on which the V warp is wound, a positive let-off for actuating the warp beam to let-oil the warp, a warp tension equalizer mounted for rectilinear movement towards and from the front of the loom, a warp guide between the warp beam and equalizer for directing the warp in parallel runs about the equalizer from full to empty beam, a weight, a connection between the weight and warp tension equalizer for causing the weight to act upon the warp tension equalizer in a direction to elongate the parallel runs of the warp loop and maintain a uniform tension upon the warp throughout the weaving operation, let-off controller shaft, connections bctween the let-off controller shaft and equalizer for causing rotation ot' the controller shaft by movements of the equalizer towards and from the front of the loom to regulate the operationof the positive let-oil and let-oft the warp through rotative movement of the controller shaft.

in a loom, the combination of the warp beam on which. the 'arp is wound, a posi 'o let-off for turning the warp beam to let-ot'i' the warp, a warp tension equalizer i'nounted for movement towards and from the front of the loom, means for guiding the warp tension equalizer in its movements, :1 warp guide between the warp beam and equalizer for directing and maintaining the warp in parallel runs about the warp tension equalizer H from full to empty beam, a weight, a flexible inember connected to the warp tension equalizer and to the weight, guiding means for the flexible member between the warp tension equalizer and weight to cause the flexible member to exert a pull upon the warp tension equalizer and maintain uniform tension of the warp throughout the weaving operation. and a let-ofl controller actuated by the flexible member to vary the posiiivc rotative movement of the warp beam without varying the uniform tension of the warp.

4:. In a let-off mechanism for looms, the combinationof the warp beam on which the warp is wound, a positive let-off for turning the warp beam to let-off the warp, a warp tension equalizer mounted for movement in a substantially horizontal plane towards and from the front of the loom, means for directing the warp in parallel planes about the equalizer, a weight normally acting upon the equalizer in a direction to maintain uniform tension on the warp during weaving, means for checking too free movement of the equalizer under the stress of the warp and weight, and means governed by substantially horizontal movement of the warp tension equalizcr to control the positive rotating movement of the warp beam without changing the uniform tension of the warp.

5. In a let-oil mechanism for looms, the

combination of the warp beam on which the warp is wound, a positive let-off for'turning the warp beam to 'let-ofl:' the warp, a warp tension equalizer constituted as a roll extending transversely of the loom, brackets at each side of the loom provided with guideways in which the equalizer has movement towards and from the front of the loom, a warp guide mounted in said brackets between the warp beam and equalizer for directing and maintaining the warp in parallel runs about the warp tension equalizer as the diameter of the warp Varies, a weight, a flexible member connecting the weight and equalizer, guides about which the flexible member passes between the weight and equalizer to cause the equalizer to pull rearwardly in the loop of the warp with a tendency to elongate the parallel runs of the loop and maintain uniform tension on the warp throughout the weaving operation, and means governed by movement of the equalizer toward and from the front of the loom for controlling the positive let-off without varying the warp tension.

6. In a let-off mechanism for looms, the combination of a warp beam on which the warp is wound, a positive let-off for rotating the warp beam to let-ofi' the warp, a Warp tension equalizer constituted as a roll extending transversely of the loom and mounted for movement towards and from the front of the loom, means for directing the warp in parallel runs about the equalizer, a weight and flexible connection between the weight combination of a warp beam on and-equalizer acting a direction to maintain uniform ten'sion on-thefw'arp throughout the weaving operation; and a let-off con trolling shaft actuated by the flexible conneetion upon movement of the-equalizer Y to-v,

wards and from-the front of thewloom'ito regulate the operation of the positive let off and lBbOfi'tlIG-WEIIP without varying'the uniformtension of the'warp.

tending transversely of the loom and mounted for movement towards and from thefront of the loom, a check for retarding too free movement of the equalizer towards and from the front of the 100m, means'for directing the warp in parallel runs about the equal-V izer, a weight and flexible connection between the weight and equalizeracting in .a direction to maintain uniform tensionon'thewarp throughout the weaving operation, and a letoif controlling shaft a-ctuatedby the flexible connection upon movement of the equalizer.

towards and from the front of the loom to regulate the operation of thepositive let-01f and let-off the warp without varying the unij. form tension of the warp.

8. In a let-off mechanism for looms, the combination of the warp beam on which the warp is Wound, a positive let-ofl' for rotating the Warp beam to let-ofi the warp, awarp ten- :sion equalizer mounted for movement towards and from'the front of the loom, a weight and a flexible member between the, weight and warp tension equalizer, a guide for the flexible member rearward of the warp tension equalizer to cause the-weight to act upon the equalizer in a rearward direction to maintaln uniform tension on the Warp throughout the weaving operation, and a let ofi controller shaft. engaged and operated J: by the flexible member as the equalizer moves toward or from the front of the loom for controlling the positive let-off torotate tension of the warp. V r

9. In a loom, the combination of the Warp beam on whichthe warpiswound, arpositive the warp beam without varying the uniform let-off for turning the warp beam to let-off the Warp, a Warp tension equalizer mounted for 'movement towards a nd 'from the front iiof the loom, means for guiding the Warp tension equalizer in its movements, means for directing the warp in parallel runs about the warp tension equalizer, a weight, arflexible member connectedto the warp tension equal- Zizer and'to the Weight, guiding means for the flexible memberbetweenthe warp tension equalizer and weight to cause the flexible 7 member to exert a pull upon the warp tension equalizer and maintain uniform tension of v equalizer a check for preven'ting-too free: movement of the warp tension equaliz'er under "the stress of the and Weight,--'and means 7 governedfby movement of the warp tension equalizer towards and from the front of the "loom to vary the positive rotative movement of the warp'beam-without varying the uniform tension of thewarp.

combination-of the warp beam, a positive let-"01f for rotating the warp beam to let-01f the {warma bracket ateach sideof: the loom having a guidewav, :a

guide way towards and from the front of the loom, a warp tension 'equalizer ounted in said, blocks, means for directing the warp block m'ovable in each in parallel runs about the "avarp tension equalizerpaiweight and-a flexible member connecting the weight and warp tension equalizer j to i maintain uniform tension -on the warp throughout the weavlng operation,

and a fric'tioncheck connected toeach block for retarding its movement 7 towards and from ith'e front of [the loom [in the guide wa'yt 11. In a let-off mechanism for looms,"the' combination of thewarp beamon which the warp is W'OllIld, a positive let-ofi Ifor actuating'thewarobeam to ilet ofi' the wave, a warp tensionrequalizer amounted for movement towardsand fromzthe front of the loom, means for directing andlmaintainin'gthe warp in parallel IlIIIS about the warp tension iequalizer as llDYIHOVGS' towards and. from the front of ith'esleom, la weight normally active upon the Warp tensi'onflequalizer in adirection to of the warp loop 1 elongate'ithe" parallel runs at r and maintain :iuni form tension on the warp,

duringmvariations in-lrthe" diameter of the warp massfon the 'beam and lmeans forimaintaining the warp tensionequalizer in parallel relation to the axis of the warp beam :as the equalizerlmoves' towards and-from the front of1the -loom.'

12.. Int let-off mechanism; for looms, the.

combination of- ;the warpqbeampa positive let-1015f for'rotating the Warpibeam to let-off the :warp',' a bracket at e ch. side of the loom having a guideway, a warp tension equalizer mounted in said ggu'ideways v for movement towards "from ft hefront of "the loom,

means .for directing the warp in parallel runs 'about'the' warp tension equalizer, a

Weight, "flexible;connection between the; weight f anfd one end; off the warpg tensiontofimaintain uniform tension, on

the war a ftransversly[ extending; shaft amounted inglthegbrackets rotated by m me iea-i -fie e con t n a se nid fi x le-lce nectionb we n:th appo i 7 end offthe equalizer and positive let-01f and movable by rotation] of the transversely extending steam 'maintain: the equalizer in; t p'arallelYire'lation toithe -warp .beamgand to .iithe Warp throughout the :weaving operation,

let-Leif theiwarp :resoonsive'to movement :of

' the front of the loom, means for directing the warp in parallel runs about the warp tension equalizer, a weight, a sprocket chain connected to the weight and to one end of the warp tension equalizer to maintain uniform tension on the warp, a transversely extending shaft having a sprocket wheel about which the sprocket chain passes and by which the shaft is rotated by movement of the sprocket chain, a second sprocket wheel rotatable by the transversely extending shaft, a second sprocket chain connected to the other end of the warp tension equalizer and passing about the second sprocket wheel to maintain the equalizer in parallel relation to the warp beam, and a positive let-off governed by the second sprocket chain to letofi the warp responsive to the equalizermovement without varying, the tension on the warp.

14. In a let-off mechanism for looms, the combination of the warp beam, a bracket at each side of the loom having a guideway, a warp tension equalizer mounted in said brackets for movement towards and from the front of the loom, a weight connected to the warp tension equalizer exerting a tendency to lengthen the parallel runs of the warp loop to maintain uniform tension 011 the warp, means for changing the position of the brackets in accordance with the lead of the warp from the equalizer towards the front of the loom, a warp guide mounted on the bracket between the warp beam and equalizer to maintain the upper and lower runs of the warp in parallel relation as the position of the brackets is changed, a positive let-off, and means controlled by move-' ment of the warp tension equalizer towards and from the front of the loom for govern ing the amount of warp let-oflt' from the warp beam without varying the warp tension.

15. In a positive let-off mechanism for looms, the combination of the warp beam on which the warp is wound, a pivoted bracket at each side of the loom having a guideway, awarp tension equalizer constituted as a roll mounted in the guideway of the brackets for bodily movement in a rectilinear path towards and from the front of theloom, a warp guide mounted in said brackets below the path of movement of the warp tension equalizer for directing the warp in a loop about the equalizer, means for adjusting the brackets about their pivotal mountings to bring the upper run of the warp into parallelism with the lower run, a weight normally acting upon the warp tension equalizer to maintain uniform tension on the warp from RICHARD A. KEARSLEY. 

